#include "light/light.h"
#include "scene/scene.h"
#include "shader/lambertshader.h"

LambertShader::LambertShader(Color const &diffuseColor) : diffuseColor(diffuseColor) {}

Color LambertShader::shade(Scene const &scene, Ray const &ray) const {
  Color fragmentColor;

  // IMPLEMENT ME
  for (auto& light : scene.lights()) {
      auto illum = light->illuminate(scene, ray);
      auto lightAngle = dotProduct(ray.normal, normalized(illum.direction));
      fragmentColor += illum.color * std::abs(lightAngle);
  }
  return fragmentColor * diffuseColor;
}